Pittsburg Alleghany® Ground Thread Pulley Tap, Measuring System: SAE, Tap Style: Plug, 1/2"", 20 Pitch, Pitch Diameter Limits: H3, 1-21/32"" Thread Length, 4 Flute, Long Shank Type, 0.507"" Shank Diameter, Right Hand Cutting Direction, 12"" Overall Length, High Speed Steel